Adjustable slab form support for bridge decking or the like

ABSTRACT

A tubular member having an internal thread is mounted on the lower flange of an I-beam. The lower end of a threaded rod is positioned within the tubular member while the upper end of the threaded rod passes through a joist and is secured thereto for supporting the forms in which concrete is to be poured. An adjusting nut and a lock nut are mounted on the threaded rod so that the height of the joist may be varied with respect to the flanges of the I-beam.

United States Patent Roth 1 1 June 5, 1973 54 ADJUSTABLE SLAB FORM SUPPORT 2,344,841 3 1944 Weber ..249 24 FOR BRIDGE DECKING OR THE LIKE 3,286,972 11/1966 Jack son ..248/228 Inventor: Irving Roth Elmont, NY. 3,584,825 6/1971 Williams .249/23 [73] Assignee: Slattery Associates, Inc., Maspeth, Primary Examiner-Marion Parsons, Jr.

'Y- Att0rneyLeonard H. King 22 F'] d: N 10, 1971 I 1 57 ABSTRACT [21] App1.No.: 199,072

A tubular member havlng an internal thread 18 mounted on the lower flange of an I-beam. The lower [52] U.S. Cl. ..248/228, 52/365, 249/24 end of a threaded rod is positioned within the tubular [51] Int. Cl ..E04g 17/18 member while the upper end of the threaded rod [58] Field of Search ..248/228, 354 S, 405; passes through a joist and is Secured thereto for 52/365; 249/23 25 porting the forms in which concrete is to be poured. An adjusting nut and a lock nut are mounted on the [56] Rein-en? C'ted threaded rod so that the height of the joist may be UNITED STATES PATENTS varied with respect to the flanges of the I-beam.

1,976,595 10/1934 Asleson ct a1. ..248/228 5 Claims, 3 Drawing Figures BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates generally to construction work and more particularly to improved means for adjusting the relative height of the forms used in concrete bridge decking or the like.

2. Description of the Prior Art When pouring concrete that will form a roadway of a bridge, for example, forms are used to contain the non-rigid concrete mass. Transverse joists are used to support longitudinal stringers which in turn support a sheet of plywood. Preferably, the lumber used in fabricating the forms is reusable so as to minimize the costs of construction. In order to insure the proper grade and to accurately level the roadbed, the prior art has provided many complicated and costly structures. In many instances, the adjustment structure used in the prior art relied on a lower surface for support thereof but this is not always convenient and in many instances is not available. Still other drawbacks of the prior art is that in many instances the structure remained in the finished concrete and was not recoverable thus substantially raising the cost of construction.

SUMMARY OF THE INVENTION The present invention obviates the shortcomings of the prior art noted above in that the adjustment means for the joists that support the frame form is located on the lower flange of the I-beam that supports the concrete roadbed. The adjustment means of this invention includes an internally threaded, tubular column in which a threaded rod is disposed. The threaded rod extends through and supports the joist on which the concrete form is located. Means are provided for preventing relative rotation of the tubular column as well as a locking nut and an adjusting nut.

Accordingly, it is an object of the present invention to provide improved means for adjusting the height of the form used when a concrete roadbed is poured.

Another object of the present invention is to provide improved adjustment means, as described above, that utilizes the structural I-beam used in bridge decking for support.

Still another object of the present invention is to provide threadable adjustment means for varying the height of the joist that supports the concrete form used in a bridge deck or the like.

These and other objects, features and advantages of the invention will, in part, be pointed out with particularlity and will, in part, become obvious from the following more detailed description of the invention, taken in conjunction with the accompanying drawing, which forms an integral part thereof.

BRIEF DESCRIPTION OF THE DRAWING In the various figures of the drawing, like reference characters designate like parts.

FIG. 1 is a fragmentary elevational view, in section, illustrating typical prior art structure;

FIG. 2 is a fragmentary elevational view, in section, illustrating one embodiment of the present invention; and

FIG. 3 is a sectional plan view taken along line 33 of FIG. 2.

DESCRIPTION OF THE PREFERRED EMBODIMENT The present invention may best be understood by first discussing a typical example of the prior art structure that is presently being used. There is provided a conventional I-beam 10 having upper and lower flanges 12 and 14, respectively, with a connecting web 13 therebetween. A post 16 is provided with straps 18 on opposite faces thereof for supporting a joist 20 on which stringers 22 and a plywood sheet 24 are mounted. A pair of wedges 26a and 26b positioned between the lower end of the post 16 and the flange 114 of the I-beam 10 for providing vertical adjustment of the joist 20. Locking wedges 28a and 28b are positioned between the top surface of the joist 20 and the top flange 12 of the I-beam 10. As is well known, the adjustment wedges 26a and 26b are manipulated so as to move the post 16 either upwardly or downwardly. This, in turn, moves the joist 20, the stringers 22 and the plywood sheet 24 either upwardly or downwardly. Once the desired position is achieved, the locking wedges 28a and 2812 are driven into place. It will be appreciated, however, that a considerable force must be applied to the adjustment wedges 26 and to the locking wedges 28. It will also be appreciated that achieving a very fine adjustment is, therefore, very difficult with the prior art structure.

FIG. 2 and FIG. 3 illustrate the adjustment device comprising the present invention. A tubular column 30, having internal threads 32, is mounted on the lower flange 14 of the I-beam 10. Means are also provided for preventing the tubular 30 from rotating and, in its simplest form, the anti-rotation means may comprise a nut 34 welded to the top of the tubular column 30 and a strap 36 welded to the nut. As shown, particularly in FIG. 3, the strap 36 bears against the web 13 of the I- beam 10 and is thereby prevented from rotating. It should be understood, however, that other equivalent anti-rotation means may also be employed.

A continuously threaded rod 38 is positioned within the tubular column 30 in mating engagement with threads 32 thereof and has a nut 4t welded thereto in any suitable location above the tubular column 30. The nut 40 provides convenient means for rotating the threaded rod 38 by means of a wrench or the like.

A joist 42 is provided with a clearance hole 44 therethrough for receiving the rod 48. An adjusting nut 46 and a washer 48 are positioned below the joist 42 and a locking nut 50 and a washer 52 are positioned above the joist 42. The threaded rod is in mating engagement with both of the nuts 46 and 56. In a conventional manner, stringers 54! are mounted on the top surface of the joist 42 and a plywood sheet 56 is mounted on the stringers 54. I

When an adjustment in the relative height of the concrete form is required, the nut 46 is rotated while the nut 40 is held stationary. Thus the nut 46 advances axially relative to the threaded rod 38 and thereby either raises or lowers the joist 42. When the proper position has been achieved, the nut 50 is tightened, thereby clamping the joist 42 between the opposed washers 48 and 52. It will be appreciated that a generally axial force'is applied directly to the joist 42 in a vertical plane from a position therebelow. This is in contrast to the prior art wherein only a vertical component of the wedging force is applied to the joist. In addition, be-

cause movement is achieved by threading the nut 36 along the rod 38, the adjustment of the joist 42 can be made much finer than was possible with the prior art structure and is limited only by the accuracy of the threads.

There has been disclosed heretofore the best embodiment of the invention presently contemplated. However, it is to be understood that various changes and modifications may be made thereto without departing from the spirit of the invention.

What I claim as new and desire to secure by Letters Patent is:

1. Means for vertically adjusting the height of a concrete form relative to a structural member such as an I-beam or the like, said adjustment means comprising:

a. a first internally threaded tubular support column mounted on the lower flange of the I-beam;

b. a second support member comprising a threaded rod mounted on said support column;

c. adjustment means comprising a nut threadably engaging said second support member and arranged to move axially relative thereto, said adjustment means bearing against the lower surface of said form; and

d. locking means comprising a nut threadably engaging said second support member and arranged to bear against a surface of the form opposite to the surface against which said adjustment means bears.

2. The adjustment means in accordance with claim 1 wherein there is further included first anti-rotation means integral with said rod.

3. The adjustment means in accordance with claim 1 wherein said first anti-rotation means is a nut rigidly secured to said rod.

4. The adjustment means in accordance with claim 2 wherein there is further included second anti-rotation means for said first support column.

5. The adjustment means in accordance with claim 4 wherein said second anti-rotation means comprises an elongated strap having one end thereof rigidly secured to said first support column, the other end of said strap being arranged to bear against the web of said I-beam. =l =l 

1. Means for vertically adjusting the height of a concrete form relative to a structural member such as an I-beam or the like, said adjustment means comprising: a. a first internally threaded tubular support column mounted on the lower flange of the I-beam; b. a second support member comprising a threaded rod mounted on said support column; c. adjustment means comprising a nut threadably engaging said second support member and arranged to move axially relative thereto, said adjustment means bearing against the lower surface of said form; and d. locking means comprising a nut threadably engaging said second support member and arranged to bear against a surface of the form opposite to the surface against which said adjustment means bears.
 2. The adjustment means in accordance with claim 1 wherein there is further included first anti-rotation means integral with said rod.
 3. The adjustment means in accordance with claim 1 wherein said first anti-rotation means is a nut rigidly secured to said rod.
 4. The adjustment means in accordance with claim 2 wherein there is further included second anti-rotation means for said first support column.
 5. The adjustment means in accordance with claim 4 wherein said second anti-rotation means comprises an elongated strap having one end thereof rigidly secured to said first support column, the other end of said strap being arranged to bear against the web of said I-beam. 